Interesting examples of discrete stochastic games
Some of the domains in the International Probabilistic Planning Competition, such as the Wildlife Preserve benchmark, fit quite well the constraints you have given. Note that the problems are modeled with a high-level declarative language, RDDL. This means that you can define problems as big or as small as your heart desires with relative ease, since you can parametrize state description in terms of functions describing properties of an arbitrary number of objects.

There's also a quite useful project that allows to instance OpenAI gym environments from the declarative description of the environment, states and actions.